Digital video services have enabled improved quality video signal transmission, resulting in an immaculate video display at the consumer end. Among various video coding standards available, Moving Picture Experts Group-2 (MPEG-2) is very popular, as it can be applied to diversified bit rates and sample rates. Additionally, the MPEG-2 video coding standard provides mature and powerful video coding methods and supports scalability.
In order to cater to newer transmission media such as Cable Modem, xDSL, or UMTS, H.264/Advanced Video Coding (AVC) standard is gaining popularity as the basis of digital video transmission. This is because of its higher coding efficiency, lower bit rate, efficient bandwidth utilization, error resilience, low processing delay, support for scalability, and capability to produce high quality video. Moreover, H.264/AVC enables transmission of more video channels or higher quality video representations within the existing digital transmission capacities.
With the advent of a variety of end user devices and time varying networks, video adaptation on the various end user devices for appropriate video presentation has become very critical. For example, in broadcast, simulcast, or multicast transmissions, the same signal may be received by various end user devices, such as televisions, cell phones, computing devices, etc. The end user devices can have different characteristics in screen sizes, life span of power supplies, memory capabilities, CPU's, etc. This makes the task of video adaptability on the targeted end devices very challenging even while using the video coding standards such as MPEG-2, H.264/AVC, etc.
As a result, scalable video coding schemes are emerging that make it possible to adapt the bit rate and quality of a transmitted stream to the network bandwidth on which the stream is transmitted. The Scalable Video Coding or SVC standard has been developed as an extension to the H.264/AVC standard. Among several scalabilities, spatial scalability, i.e. video adaptability through different spatial resolutions, is one of the key features generally required in scalable video streaming over heterogeneous devices such as mobile phones, televisions, personal digital assistants (PDAs), laptops, and so on. However, appropriate techniques for achieving spatial scalability and producing a scalable video signal subsuming multiple distinct resolutions from a non-scalable video signal are currently unavailable.